The Colorado 13er List

1. Rank.
   A summit has a hard rank, if it has at least 300 feet of Prominence. Prominence is given in the Prom column, and a right-justified number in the Rank column means that the summit has a hard rank. Summits that do not have a hard rank but could rank if extrapolated elevations were not used for the summit and/or interpolated elevations were not used for the Prominence Saddle, have a soft rank. Summits with a soft rank have a left-justified S in the Rank column. No entry in the Rank column means that the summit is named but unranked. I list ranked summits whether they are named or not.
    
2. Elevation
   The exact or estimated elevation of the summit.
    
3. Prominence.
   The Prominence of a summit in these lists is its rise above the highest saddle connecting the summit to higher ground. This highest saddle is called the Prominence Saddle, which I have previously called the Connecting Saddle. Thus, Prominence is the elevation of the summit minus the elevation of the Prominence Saddle. Prominence is a pure topographic measure that is independent of names, parents, and ranks. Occasionally, a summit does not have a given elevation, and in these cases, the summit elevation is calculated by extrapolating above the summit’s highest closed contour by half the contour interval. Often, a saddle does not have a given elevation, and in these cases the saddle elevation is interpolated between the highest contour that does not go through the saddle and the lowest contour that does go through the saddle. Given elevations in a saddle are used, but only if they represent the low point of the saddle. The maps used for calcutaing Prominence are the largest scale (most detailed) maps available for the region. In Colorado, these are the the USGS 7.5 minute quadrangles, which typically have a contour interval of 40 feet in the mountains. In these lists, Prominence is given in feet.
    
4. Summit Name.
   A peak qualifies for a list if it is named or ranked. Named summits are on a list if they are ranked or unranked. The officially named summits include peaks, mounts, mountains, named ridges, named benchmarks if they do not have a peak name, named rocks, named hills, and other named features such as moraines. I enclose unofficial names in double quotation marks. If a summit has both a peak name and a named benchmark, the peak name takes precedence.
   
    
5. Parent.
   The closest, higher, hard ranked summit is the Proximate Parent. The closest, higher, hard ranked summit that one would reach by climbing beyond and above the Prominence Saddle is the Prominence Parent. The term Line Parent is a synonym for Prominence Parent. For most summits, the Proximate and Prominence Parents are the same peak, and in these cases, I list that peak name once in the Parent Column. When the Proximate and Prominence Parents are two different peaks, I list the Proximate Parent first followed by the Prominence Parent on a second line. Unranked summits still have parents.
   
    
6. Isolation.
   The Great Circle distance between a summit and its Proximate Parent is the summit’s Isolation. I list this distance in miles in the Iso column. When a summit has different Proximate and Prominence Parents, I list the Great Circle distance to each parent adjacent to the parent names in the Parent column. By definition, the distance to the Proximate Parent will always be less than or equal to the distance to the Prominence Parent. The distance to the Proximate Parent is the summit’s Isolation, but I include the distance to the Prominence Parent as additional information.
    
7. Quadrangle
   The main USGS map "quadrangle" where the summit is located.
    
8. Range
   The mountain range in which the summit is located:
       FR - Front Range
       TM - Tenmile Range and Mosquito Range
       EL  - Elk Mountains
       SW - Sawatch Range
       SJ  - San Juan Mountains
       SC - Sangre de Cristo Range
       GO - Gore Range
    

Note: When two or more summits have the same elevation, they are ordered by decreasing Prominence. If there are peaks with the same elevation and prominence, then they are ordered by decreasing Isolation.